by F. Giacco, L. Saggese, DE ARCANGELIS Lucilla, LIPPIELLO Eugenio, M. Pica Ciamarra
Abstract:
The unexpected weakness of some faults has been attributed to the emergence of acoustic waves that promote failure by reducing the confining pressure through a mechanism known as acoustic fluidization, also proposed to explain earthquake remote triggering. Here we validate this mechanism via the numerical investigation of a granular fault model system. We find that the stick-slip dynamics is affected only by perturbations applied at a characteristic frequency corresponding to oscillations normal to the fault, leading to gradual dynamical weakening as failure is approaching. Acoustic waves at the same frequency spontaneously emerge at the onset of failure in the absence of perturbations, supporting the relevance of acoustic fluidization in earthquake triggering.
Reference:
Dynamic Weakening by Acoustic Fluidization during Stick-Slip Motion (F. Giacco, L. Saggese, DE ARCANGELIS Lucilla, LIPPIELLO Eugenio, M. Pica Ciamarra), In PHYSICAL REVIEW LETTERS, volume 115, 2015. (Articolo in rivista)
Bibtex Entry:
@article{gia15,
author = {F. Giacco, and L. Saggese, and DE ARCANGELIS Lucilla, and LIPPIELLO Eugenio, and M. Pica Ciamarra,},
pages = {1-5},
title = {Dynamic Weakening by Acoustic Fluidization during Stick-Slip Motion},
volume = {115},
note = {Articolo in rivista},
issn = {0031-9007},
journal = {PHYSICAL REVIEW LETTERS},
doi = {10.1103/PhysRevLett.115.128001},
url = {http://link.aps.org/doi/10.1103/PhysRevLett.115.128001},
year = {2015},
wosId = {WOS:000361315300008},
scopusId = {2-s2.0-84942154752},
abstract = {The unexpected weakness of some faults has been attributed to the emergence of acoustic waves that
promote failure by reducing the confining pressure through a mechanism known as acoustic fluidization,
also proposed to explain earthquake remote triggering. Here we validate this mechanism via the numerical
investigation of a granular fault model system. We find that the stick-slip dynamics is affected only
by perturbations applied at a characteristic frequency corresponding to oscillations normal to the fault,
leading to gradual dynamical weakening as failure is approaching. Acoustic waves at the same frequency
spontaneously emerge at the onset of failure in the absence of perturbations, supporting the relevance of
acoustic fluidization in earthquake triggering.}
}